Most current spray foam insulation liquid compositions are based on two components, a polyol component and an isocyanate component that are separate until the time of application. The isocyanate is typically composed of methylene diphenyl diisocyanate (MDI), which when aerosolized exists as very fine airborne droplets. Exposure to aerosolized MDI can pose a severe health threat (e.g., allergic sensitization). Accordingly, there exists a need for spray foams that eliminate the use of MDI and provide systems safer to the applicator and to nearby personnel.